ADV Films has released two DVDs of the series in the US; A Hero is Born
contains season 1, while Battle for the Future is season 2 and that one
episode people say is from a discontinued season 3 but I think they're just
talking crazy talk. The two sets have leapt in price significantly over the
years, and those that have it haven't even been cool enough to torrent it or
anything, so YouTube is probably your best bet for watching it if you don't want
to lose an arm and a leg.

Fun fact! The box art you see everywhere for A Hero Is Born (and here too
due to laziness) is actually the art used on the disc!